The present invention is directed to a hydraulic tool for pushing together opposing members which are laterally offset from the axis of the hydraulic cylinder. It is particularly useful for assembling tubular components to form a permanent tube joint of a type where a constrictor ring with a tapered bore is axially forced over a collar encircling the end of a tube to cause local annular compression of the collar and the encircled tube. Tube joints of this type are shown in a number of prior art patents including U.S. Pat. Nos. 3,827,727; 4,026,006 and 4,482,174. Tube joints of this type require significant amounts of axial force to cause the constrictor ring to be moved axially over the collar member while radially compressing and deforming it and the tube encircled by such collar.
U.S. Pat. No. 4,189,817 discloses a hydraulic assembly tool for tube fittings which may be used for assembling the components of the tube joints described in such patents. Although hydraulic assembly tools of the type described in U.S. Pat. No. 4,189,817 have the ability to assemble such components, the mechanical inefficiencies, primarily due to friction, associated with that design cause the prior art tools to be larger than necessary and to have limited service lives.